The average 5-year survival for colorectal cancer (CRC) is less than 10% if metastasis occurs, but can reach 90% if detected early. A new non-invasive test has been developed that measures methylation of the SDC2 gene in tissues and blood sera.
This test detected 87% of all stages of colorectal cancer cases (sensitivity) without significant difference between early and advanced stages, while correctly identifying 95% of disease-free patients (specificity). The results are published in the July issue of The Journal of Molecular Diagnostics.
According to the US Centers for Disease Control and Prevention, CRC is the second leading cancer killer in the US affecting both men and women. In 2009, close to 137,000 people in the US were diagnosed with CRC, with close to a 40% mortality rate.
There are other screening choices for CRC, including fecal occult blood testing (FOBT), fecal immunochemical testing, and colonoscopy. Colonoscopy is the gold standard of CRC screening, but patient resistance – mostly due to the unpleasant preparation – has curbed widespread adoption. FOBT is non-invasive but has limited sensitivity, particularly for early disease. A sensitive and specific non-invasive test using blood or stool could to be a more preferable option with the potential of saving many lives.
In their search for a biomarker that could be used for the early detection of CRC, investigators from Genomictree, Inc. and Yonsei University College of Medicine in Seoul, South Korea, performed DNA microarray analysis coupled with enriched methylated DNA using tissues from primary tumors and non-tumor tissues from 12 CRC patients. After step-wise filtering, they found a set of genes that were highly methylated across all of the CRC tumors. Ultimately they identified one gene, SDC2, which encodes the membrane syndecan-2 protein, a protein that is known to participate in cell proliferation, cell migration, and is expressed in colon mesenchymal cells. The methylation level of target region of SDC2 assessed in tumor tissue was found to be significantly higher than that from paired adjacent non-tumor tissue.
The next step was to clinically validate the biomarker by analyzing SDC2 methylation levels in primary tumors and paired-adjacent non-tumor tissue samples from 133 CRC patients. Investigators found that in the transcriptional regulatory region of the SDC2 gene, tumor samples showed significantly higher levels of methylation than the control samples. SDC2 methylation positivity ranged from 92.9% to 100% when samples were stratified according to stages of cancer.
Further, investigators found that the SDC2 biomarker could be measured in serum samples from CRC patients and healthy individuals. "The SDC2 methylation test was able to detect 92% for detection of stage I cancer patients indicating that SDC2 is suitable for early detection of CRC where therapeutic interventions have the greatest likelihood of curing the patient from the disease," says first author TaeJeong Oh, PhD.
The authors suggest that the SDC2 methylation test they describe could possibly be used as an alternative to or in conjunction with colonoscopy. It could also be used to monitor cancer progression and treatment. Dr. Sungwhan An, corresponding author and CEO of Genomictree, Inc., commented: "We are very excited with this result using a small amount of serum DNA from less than 1ml of blood. I believe a greater volume of blood will further improve the clinical performance of this test. We are currently preparing another set of clinical validation studies evaluating SDC2 methylation in serum DNA from patients with early adenoma." In future research the authors will explore whether this biomarker is specific to CRC or universal among other cancers.
David Sampson | EurekAlert!
A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences